The search for new physics by the measurement of the 4-jet cross section at LHC and FNAL

We investigate the possibility to look for new physics by the measurement of the 4-jet cross section at LHC and FNAL. In particular, we consider the model with scalar colour octet and the supersymmetric model with R-parity violation. In both models pair produced new particles decay into 2 jets thus leading to 4-jet events. Therefore, the measurement of the distributions of 4-jet differential cross section on the invariant dijet masses allows to look for new physics. The main background comes from standard QCD 4-jet events. We find that at LHC it would be possible to discover scalar colour particles with masses up to 900 Gev and for FNAL the corresponding bound is 175 Gev.